Pinpoint Test T: Intermittent No Medium Speed Controller Area Network (MS-CAN) Communication, Communication Can Be Intermittent
Communications Network
Pinpoint Tests
Pinpoint Test T: Intermittent No Medium Speed Controller Area Network (MS-CAN) Communication, Communication Can Be Intermittently Established
Normal Operation
The Medium Speed Controller Area Network (MS-CAN) uses an unshielded twisted pair cable. Circuits VDB06 (GY/OG) and VDB07 (VT/OG) provide the network connection to all modules on the network. In the event that 1 of the 2 network circuits (MS-CAN + or MS-CAN -) becomes open to a module on the network, unreliable network communication to all modules on the network may result.
The following modules communicate with the scan tool using the MS-CAN:
- Accessory Protocol Interface Module (APIM)
- Audio Control Module (ACM)
- Audio Digital Signal Processing (DSP) module
- Driver Seat Module (DSM)
- Front Controls Interface Module (FCIM)
- Front Display Interface Module (FDIM)
- HVAC module
- Instrument Cluster (IC)
- Liftgate/Trunk Module (LTM)
- Parking Aid Module (PAM)
- Rear Entertainment Module (RETM)
- Smart Junction Box (SJB)
This pinpoint test is intended to diagnose the following:
- Wiring, terminals or connectors
PINPOINT TEST T: INTERMITTENT NO MS-CAN COMMUNICATION, COMMUNICATION CAN BE INTERMITTENTLY ESTABLISHED
NOTE: Most faults are due to connector and/or wiring concerns. Carry out a thorough inspection and verification before proceeding with the pinpoint test. Inspection and Verification
NOTE: Various network DTCs will set while disabling modules in this test procedure which will need to be cleared after the diagnostic procedure is completed.
NOTE: Failure to disconnect the battery when instructed will result in false resistance readings. Refer to Battery.
-------------------------------------------------
T1 CHECK THE DLC PINS FOR DAMAGE
- Ignition OFF.
- Disconnect the scan tool cable from the Data Link Connector (DLC).
- Inspect DLC pins 3 and 11 for damage.
- Are DLC pins 3 and 11 OK?
Yes
GO to T2.
No
REPAIR the DLC as necessary. CLEAR the DTCs. REPEAT the network test with the scan tool.
-------------------------------------------------
T2 CHECK THE MS-CAN TERMINATION RESISTANCE
- Disconnect: Negative Battery Cable.
- Measure the resistance between the DLC C251-3, circuit VDB06 (GY/OG), harness side and the DLC C251-11, circuit VDB07 (VT/OG), harness side.
- Is the resistance between 54 and 66 ohms?
Yes
GO to T3.
No
Go To Pinpoint Test U. Pinpoint Test U: No Medium Speed Controller Area Network (MS-CAN) Communication, All Modules Are Not Responding
-------------------------------------------------
T3 CHECK THE MS-CAN (+) AND MS-CAN (-) CIRCUITS FOR A SHORT TO GROUND
- Measure the resistance between the DLC C251-3, circuit VDB06 (GY/OG), harness side and ground; and between the DLC C251-11, circuit VDB07 (VT/OG), harness side and ground.
- Are the resistances greater than 1,000 ohms?
Yes
GO to T4.
No
Go To Pinpoint Test U. Pinpoint Test U: No Medium Speed Controller Area Network (MS-CAN) Communication, All Modules Are Not Responding
-------------------------------------------------
T4 CHECK THE MS-CAN (+) AND MS-CAN (-) CIRCUITS FOR A SHORT TO VOLTAGE
- Connect: Negative Battery Cable.
- Ignition ON.
- Measure the voltage between the DLC C251-3, circuit VDB06 (GY/OG), harness side and ground; and between the DLC C251-11, circuit VDB07 (VT/OG), harness side and ground.
- Is the voltage greater than 6 volts?
Yes
REPAIR the circuit in question. CLEAR the DTCs. REPEAT the network test with the scan tool.
No
GO to T5.
-------------------------------------------------
T5 CHECK FOR RESTORED NETWORK COMMUNICATION WITH THE SJB DISABLED
- Disconnect: Smart Junction Box (SJB) Fuse 5 (10A).
- Enter the following diagnostic mode on the scan tool: Network Test.
- Repeat the network test.
- Do all other MS-CAN modules pass the network test?
Yes
INSTALL the removed fuse. Go To Pinpoint Test I. Pinpoint Test I: The Smart Junction Box (SJB) Does Not Respond To The Scan Tool
No
INSTALL the removed fuse. If the vehicle is equipped with a PAM, GO to T6.
If the vehicle is not equipped with a PAM, GO to T7.
-------------------------------------------------
T6 CHECK FOR RESTORED NETWORK COMMUNICATION WITH THE PAM DISABLED
- Disconnect: SJB Fuse 35 (10A).
- Enter the following diagnostic mode on the scan tool: Network Test.
- Repeat the network test.
- Do all other MS-CAN modules pass the network test?
Yes
INSTALL the removed fuse. Go To Pinpoint Test P. Pinpoint Test P: The PAM Does Not Respond To The Scan Tool
No
INSTALL the removed fuse. GO to T7.
-------------------------------------------------
T7 CHECK FOR RESTORED NETWORK COMMUNICATION WITH THE ACM DISABLED
- Disconnect: SJB Fuse 39 (20A).
- Enter the following diagnostic mode on the scan tool: Network Test.
- Repeat the network test.
- Do all other MS-CAN modules pass the network test?
Yes
INSTALL the removed fuse. Go To Pinpoint Test K. Pinpoint Test K: The Audio Control Module (ACM) Does Not Respond To The Scan Tool
No
INSTALL the removed fuse. If the vehicle is equipped with an audio DSP module, GO to T8.
If the vehicle is not equipped with an audio DSP module, GO to T9.
-------------------------------------------------
T8 CHECK FOR RESTORED NETWORK COMMUNICATION WITH THE AUDIO DSP MODULE DISABLED
- Disconnect: Battery Junction Box (BJB) Fuse 7 (30A).
- Enter the following diagnostic mode on the scan tool: Network Test.
- Repeat the network test.
- Do all other MS-CAN modules pass the network test?
Yes
INSTALL the removed fuse. Go To Pinpoint Test L. Pinpoint Test L: The Audio Digital Signal Processing (DSP) Module Does Not Respond To The Scan Tool
No
INSTALL the removed fuse. GO to T9.
-------------------------------------------------
T9 CHECK FOR RESTORED NETWORK COMMUNICATION WITH THE FCIM DISABLED
- Disconnect: SJB Fuse 16 (15A).
- Enter the following diagnostic mode on the scan tool: Network Test.
- Repeat the network test.
- Do all other MS-CAN modules pass the network test?
Yes
INSTALL the removed fuse. Go To Pinpoint Test M. Pinpoint Test M: The Front Controls Interface Module (FCIM) Does Not Respond To The Scan Tool
No
INSTALL the removed fuse. GO to T10.
-------------------------------------------------
T10 CHECK FOR RESTORED NETWORK COMMUNICATION WITH THE IC DISABLED
- Disconnect: SJB Fuses 26 (10A) and 29 (5A).
- Enter the following diagnostic mode on the scan tool: Network Test.
- Repeat the network test.
- Do all other MS-CAN modules pass the network test?
Yes
INSTALL the removed fuses. Go To Pinpoint Test C. Pinpoint Test C: The Instrument Cluster (IC) Does Not Respond To The Scan Tool
No
INSTALL the removed fuse. GO to T11.
-------------------------------------------------
T11 CHECK FOR RESTORED NETWORK COMMUNICATION WITH THE HVAC MODULE DISABLED
- Disconnect: SJB Fuse 15 (10A).
- Enter the following diagnostic mode on the scan tool: Network Test.
- Repeat the network test.
- Do all other MS-CAN modules pass the network test?
Yes
INSTALL the removed fuse. Go To Pinpoint Test J. Pinpoint Test J: The HVAC Module Does Not Respond To The Scan Tool
No
INSTALL the removed fuse. If the vehicle is equipped with an RETM, GO to T12.
If the vehicle is not equipped with an RETM, GO to T13.
-------------------------------------------------
T12 CHECK FOR RESTORED NETWORK COMMUNICATION WITH THE RETM DISABLED
- Disconnect: SJB Fuse 3 (15A).
- Enter the following diagnostic mode on the scan tool: Network Test.
- Repeat the network test.
- Do all other MS-CAN modules pass the network test?
Yes
INSTALL the removed fuse. Go To Pinpoint Test G. Pinpoint Test G: The Rear Entertainment Module (RETM) Does Not Respond To The Scan Tool
No
INSTALL the removed fuse. GO to T13.
-------------------------------------------------
T13 VERIFY VEHICLE EQUIPMENT - DSM
- Verify whether the vehicle is equipped with a DSM.
- Is the vehicle equipped with a DSM?
Yes
GO to T14.
No
GO to T15.
-------------------------------------------------
T14 CHECK FOR RESTORED NETWORK COMMUNICATION WITH THE DSM DISABLED
- Disconnect: SJB Fuse 13 (5A).
- Enter the following diagnostic mode on the scan tool: Network Test.
- Repeat the network test.
- Do all other MS-CAN modules pass the network test?
Yes
INSTALL the removed fuses. Go To Pinpoint Test O. Pinpoint Test O: The Driver Seat Module (DSM) Does Not Respond To The Scan Tool
No
INSTALL the removed fuse. GO to T15.
-------------------------------------------------
T15 VERIFY VEHICLE EQUIPMENT - APIM, FDIM AND/OR LTM
- Verify whether the vehicle is equipped with an APIM, FDIM and/or LTM.
- Is the vehicle equipped with an APIM, FDIM and/or LTM?
Yes
GO to T16.
No
An intermittent fault is not present. Go To Pinpoint Test U. Pinpoint Test U: No Medium Speed Controller Area Network (MS-CAN) Communication, All Modules Are Not Responding
-------------------------------------------------
T16 CHECK FOR RESTORED NETWORK COMMUNICATION WITH THE APIM, FDIM AND LTM DISABLED
- Disconnect: SJB Fuse 14 (10A).
- Enter the following diagnostic mode on the scan tool: Network Test.
- Repeat the network test.
- Do all other MS-CAN modules pass the network test?
Yes
INSTALL the removed fuse. GO to T17.
No
An intermittent fault is not present. Go To Pinpoint Test U. Pinpoint Test U: No Medium Speed Controller Area Network (MS-CAN) Communication, All Modules Are Not Responding
-------------------------------------------------
T17 VERIFY VEHICLE EQUIPMENT - LTM
- Verify whether the vehicle is equipped with an LTM.
- Is the vehicle equipped with an LTM?
Yes
GO to T18.
No
GO to T19.
-------------------------------------------------
T18 CHECK FOR RESTORED NETWORK COMMUNICATION WITH THE LTM DISCONNECTED
- Disconnect: LTM C4174a.
- Enter the following diagnostic mode on the scan tool: Network Test.
- Repeat the network test.
- Do all other MS-CAN modules pass the network test?
Yes
CONNECT the LTM. Go To Pinpoint Test H. Pinpoint Test H: The Liftgate/Trunk Module (LTM) Does Not Respond To The Scan Tool
No
GO to T19.
-------------------------------------------------
T19 VERIFY VEHICLE EQUIPMENT - FDIM
- Verify whether the vehicle is equipped with an FDIM.
- Is the vehicle equipped with an FDIM?
Yes
GO to T20.
No
GO to T21.
-------------------------------------------------
T20 CHECK FOR RESTORED NETWORK COMMUNICATION WITH THE FDIM DISCONNECTED
- Disconnect: FDIM C2123.
- Enter the following diagnostic mode on the scan tool: Network Test.
- Repeat the network test.
- Do all other MS-CAN modules pass the network test?
Yes
CONNECT the FDIM. Go To Pinpoint Test N. Pinpoint Test N: The Front Display Interface Module (FDIM) Does Not Respond To The Scan Tool
No
CONNECT the FDIM. GO to T21.
-------------------------------------------------
T21 VERIFY VEHICLE EQUIPMENT - APIM
- Verify whether the vehicle is equipped with an APIM.
- Is the vehicle equipped with an APIM?
Yes
GO to T22.
No
An intermittent fault is not present. Go To Pinpoint Test U. Pinpoint Test U: No Medium Speed Controller Area Network (MS-CAN) Communication, All Modules Are Not Responding
-------------------------------------------------
T22 CHECK FOR RESTORED NETWORK COMMUNICATION WITH THE APIM DISCONNECTED
- Disconnect: APIM C3342.
- Enter the following diagnostic mode on the scan tool: Network Test.
- Repeat the network test.
- Do all other MS-CAN modules pass the network test?
Yes
CONNECT the APIM. Go To Pinpoint Test Q. Pinpoint Test Q: The Accessory Protocol Interface Module (APIM) Does Not Respond To The Scan Tool
No
An intermittent fault is not present. Go To Pinpoint Test U. Pinpoint Test U: No Medium Speed Controller Area Network (MS-CAN) Communication, All Modules Are Not Responding
-------------------------------------------------